The present invention relates to a new and improved attachment for use with a sewing machine for cutting the edges of a length of material fed to the sewing machine.
In its more specific aspects the invention relates to a new and improved cutting attachment for use with a sewing machine for cutting edges of a length of material fed to the sewing machine, said cutting attachment comprising a fixed or stationary cutter blade and a movable cutter blade drivable by means of a needle bar of the sewing machine via an articulated lever mechanism, the movable cutter blade coacting with the fixed cutter blade in the manner of a pair of scissors.
Such cutting attachments can be affixed to all types of sewing machines and various designs thereof are known for cutting the edge of the fabric material to be sewn travelling towards the sewing location. Usually the movable cutter blade driven by the needle bar is substantially vertically moved and cooperates with a counter cutter blade which is fixedly connected to a part of the sewing machine. In such an arrangement as known, for example, from Italian Pat. No. 603,617, the movable cutter blade is either directly mounted at the needle bar or at a cutter blade holder mounted on the working or operating surface of the sewing machine. In another construction of cutting attachment, as known for example, from German patent publication No. 3,122,935, either an appropriately constructed edge of the sewing foot, a cutting edge mounted thereto, or a counter cutter blade supported by the cutting attachment serves as the fixed cutter blade or counter blade.
The known cutting attachments either are complicated or cumbersome to handle in that parts of the sewing machine have to be exchanged or adjusting operations are required in order to ensure accurate cooperation of the two cutter blades. In the case of the cutting attachment according to the already mentioned German patent publication No. 3,122,935, the sewing foot has to be exchanged for the cutting attachment. Directly mounting the cutting attachment to the presser bar has the disadvantage that the cutting attachment is lifted together with the presser when thick sewing material is to be stitched and cut, so that the infeed of the sewing material and the simultaneous stitching around the edge of the material at the very least is rendered more difficult if not made impossible. Furthermore, the axis of the movable cutter blade is located directly at the cutting location and obstructs the removal of the separated or cut material. It is a further disadvantage of the known cutting attachment that the motion is transmitted through a number of hinges which, in addition to the resultant expensive manufacture, also leads to undesired wear, play and noise.